Gyroscopic stabilization can be used to maintain an otherwise unstable body in an upright position. Devices equipped with gyroscopes can balance upon a small area or point without falling over when the gyroscopic stabilizing force is greater than a rotational force or moment from an out-of-balance load that causes the device to tip. A new concept for a gyroscopically stabilized platform has been proposed in the form of a schematic diagram. The proposed system comprises of four interconnected gyroscopes that react to the tipping of an inherently unstable external body. The purpose of this research is to evolve a design for, and establish the feasibility of building the proposed stable platform using available materials and technology. If feasible, the gyroscopically stabilized platform will be made at the most practical and economic size. Louis Brennan developed a 37 tonne monorail that was maintained in the upright position with two 3 tonne counter rotating gyroscopes. The Brennan monorail is analysed to better understand the behaviour of a similar coupled gyroscopic stabilization system. The reactions between the components that maintain the monorail in the stable position are studied and comparisons are made between the proposed stable platform and the Brennan system. A mathematical analysis of the proposed system is presented. The equations of motion for the system are derived using the Lagrangian Formalism. The characteristic equation of the system is then determined and from this a set of stability conditions imposed on the design of the physical parameters of the stable platform. The general solutions to the equations of motion are then derived. Expressions that model the behaviour of two of the variables that describe the motion of the stable platform are determined. A systematic approach is adopted for establishing a new concept for the proposed system. Testing of the initial stable platform prototype (Prototype A) showed the system did not behave as intended. The platform was optimised further and this resulted in a second prototype, Prototype B. Prototype B exhibiting the desired oscillatory motion about the vertical of the platform. Predictions made using the mathematical model are compared with empirical results. The mathematical model was found to be an accurate method for predicting the response of the stable platform.

Design and analysis of polysilicon and single crystal silicon gyroscopes have been carried out. Variations in suspension design have been explored. Designs that utilize in-plane and out-of-plane sensing are studied. Damping plays an important role in determining the sense response. Reduction in damping directly affects sensor performance. The various damping mechanisms that are prevalent in gyroscopes are studied. Perforations on the proof mass are observed to significantly reduce the damping in the device when operated in air. The effects of perforation geometry and density have been analyzed. The analysis results show that there is a two orders of magnitude reduction in damping of thick gyroscope structures with optimized perforation design. Equivalent circuit lumped parameter models have been developed to analyze gyroscope performance. The simulation results of these models have been compared with results obtained from SABER, a MEMS specific system level design tool from Coventorware. The lumped parameter models are observed to produce faster simulation results with an accuracy comparable to that of Coventorware Three gyroscopes specific to the PolyMUMPS fabrication process have been designed and their performance analyzed. Two of the designs sense motion out-of-plane and the other senses motion in-plane. Results of the simulation show that for a given damping, the gyro design with in-plane modes gives a resolution of 4º/s. The out-of-plane gyroscopes have two variations in suspension. The hammock suspension resolves a rate of 25º/s in a 200 Hz bandwidth while the design with folded beam suspension resolves a rate of 2º/s in a 12 Hz bandwidth. A single crystal silicon in-plane gyroscope has been designed with vertical electrodes to sense Coriolis motion. This design gives an order of magnitude higher Capacitance change for a given rotation in comparison to conventional comb-finger design. The effects of process induced residual stress on the characteristic frequencies of the polysilicon gyroscopes are also studied. The in-plane gyroscope is found to be robust to stress variations. Analysis results indicate that the tuning fork gyroscope with the hammock suspension is the most susceptible to compressive residual stress, with a significant drop in sensitivity at high stress values.